The invention relates to a lap creel for receiving yarns, with rotationally symmetric bodies, whose exterior forms a surface supporting the yarn, with a collar projecting axially at one end, with a yarn bunching groove and a seat for the collar at the other end.
Lap creels of this type have been disclosed. These lap creels are provided with annular teeth at both ends, said teeth projecting in the axial direction. The radially outward surfaces of the teeth abut the surface of the lap creels supporting the yarn without a transition. The teeth located at one end of the lap creel are adjusted to fit the tooth spacing of the teeth at the other end. The surfaces supporting the yarn can be wound up to the area of the two sets of teeth and can cover a maximum of 50% of the total axial extent.
With axial stacking of two lap creels, the teeth, arranged annularly and opposite one another, mesh in the most favorable case, with the 50% of the teeth that are not wound being guided beneath the laps of the opposite lap creel. The laps on this creel therefore have their faces close together without any space. In this manner, slipping of the laps off the lap creel can he avoided during transport and use of the otherwise conventional intermediate disks or spacers covering the spaces can he eliminated. At the same time storage and shipping space are saved and, in the case of axial compression, assurance is provided that the pressure thus exerted is also effective between the laps, so that relative movements between the laps on the one hand and the lap creels on the other is practically eliminated. For dyeing it is also important to form a homogeneous yarn column of stacked lap creels, in which the laps have their faces pressed tightly together.
To improve the guidance between two axially adjacent lap creels, at one end of the lap creel a collar projecting axially beyond the teeth is provided on which a bunching groove can he provided and at the other end of the lap creel there is a seat adapted to the outer dimensions of the collar.
In known lap creels, despite the above-mentioned advantages, disadvantages are also clearly apparent. When the lap creels are wound, the bunching provided on the collar which is offset radially inward is wound first. The inside diameter of the lap creel however is smaller in this area than at the opposite end, which leads to problems in the creeling machines, which in the case of the other lap creels of the prior art, to the extent that these have a bunching groove, accept these at the end with the larger diameter. With such an arrangement however, the bunching groove cannot be made in a covered arrangement. If the bunching is wound on, the yarn thread must be guided onto the surface that supports the yarn and is located radially outward from the collar, in order to wind on this surface. Since the winding of the surface of the known lap creels that supports the yarn can cover only 50% of the axial distance of the teeth, a transitional area results which the thread must span by covering the remaining 50% of the teeth. In any case, with an axial stacking of adjacent lap creels and the meshing of the opposite teeth, squeezing or tearing of the thread coming from the bunching and hence a reduction in quality takes place, for example as a result of the defective dyeing that then occurs or leads to operating malfunctions when unwinding in the event of a break.
Since it is not possible for the teeth to grip below the opposite laps without tilting the lap creels, tilting of the teeth can also cause damage to the thread. The teeth also reduce the reliability of seating in the creeling device and permanent spreading can occur at this point so that when the wound lap creels are inserted into one another, the expanded teeth can penetrate the yarn. In order to wind such a sleeve, it is necessary to replace the take-up disks on winding machines by take-up disks with suitable dimensions because the known lap creel has the bunching at the end with the smaller inside diameter and hence inverted from the usual.